This question on Linguistics Stack Exchange addresses this, asking if mother and father are true antonyms. I'll quote the accepted answer, written by robert, which basically boils down to "Technically no, but sometimes yes."
Mother is not the antonym of father. They are co-hyponyms because they are both a kind of parent - and parent is the hypernym of mother and father.
Antonymy is the relation that holds between parent and child. So by extension the antonym of mother could be said to be child.
EDIT: After reading hippietrail's answer, I somewhat changed my opinion. If one considers two words to be antonyms already if just one of their semantic features is replaced with the opposite then mother (female parent) and father (male parent) can be said to be antonyms. However, I feel that it might make sense to reserve antonymy for complete negation or oppositeness, and describe the relation between mother and father as hyponymy.
One thing to keep in mind is that language textbooks are often geared toward students who are at a very basic level of that language. For someone who is just beginning to learning English, framing words like mother and father or son and daughter as opposites is a simplification that helps students learn the proper use of those terms. In a simplified way, it makes sense: a mother is a parent who is not a father, and a father is a parent who is not a mother; a son is a child who is not a daughter, and a daughter is a child who is not a son.
This simplification serves the same purpose as the simplification often taught to children just beginning to learn division that even numbers can be divided by two and odd numbers can't. Later on, when they're more advanced, the students will learn that odd numbers can be divided by two; it's just that doing so doesn't result in a whole number. At a more advanced stage, students will learn that words like father and mother aren't true opposites like hot and cold are, but at the moment, that terminology suffices.
From Eric Partridge, A Dictionary of Slang and Unconventional English, fifth edition (1961):
apple-sauce. Impudence: mostly lower middle class: late C.19–20. An elaboration of sauce, n., 1 ...
The relevant definition of sauce in Partridge is as follows:
sauce. Impudence, impertinence: coll[oquial] and dial[ectal]: 1835, Marryat (OED); perhaps much earlier (see [more] sauce than pig [defined in its own entry as "(To be) very impudent, impertinent: coll[oquial]: late C 17–18. B[ritish] E[nglish]"]. Ex saucy ...
J.E. Lighter, The Random House Historical Dictionary of American Slang (1994) offers this more elaborate, two-definition entry:
applesauce n, 1. Theat[rical] silly trite comedy [Citations, starting in 1918, omitted.] 2. nonsense, flattery, insincerity; lies—also used as interj[ection]. [First two citations:] 1919 T.A. Dorgan, in Zwilling TAD Lexicon 15: They spill a lot of applesauce about big money, 1920 in Collier's (Jan 1, 1921) 18: That's all apple sauce!
So applesauce, as used at the end of the OP's quotation simply means "baloney!"
A Google Books search doesn't find the Dorgan/Zwilling example mentioned in Lighter, but it does find two instances (both by the same author) from Collier's Magazine in 1921. From H.C. Witwer, "Auto Intoxication," in Collier's (January 1, 1921):
"Gimme my money back, you burglar!" shrieked the newcomer, ignoring me entirely. "I'm gonna have you pinched. This old tomato can is nothin' but a mess of junk! When I cranked it up last Friday mornin' the rear end fell out in the street, and the repair man tells me the only reason it ever run a foot is because you went to work and doped the motor with ether! The bearin's is all shot, it needs—!"
"Ssh!" interrupted the dealer wearily, as one who hears an old story. "That's all apple sauce! I told you the job needed the touch of a monkey wrench here and there. You can't expect to git no factory pet for what you paid for this car. They's no use gittin' hysterical, you bought the car as is, and they i absolutely no comeback. If you don't want it, leave it here and I'll sell it for you some time to-day and git you what I can for it!"
And from H.C. Witwer, "The Shooting Stars," in Collier's (June 11, 1921):
"A thousand pardons, old man!" says my vis-a-vis, climbin' out into the road. Dug, he didn't look so particularly hugely when he was scrunched up behind the steerin' wheel, but when he stood up and unfolded his full length, it was different. "You were hitting it up so fast, I had no idea you intended turning off the road here," he goes on. "However, I'll—"
""That's all apple sauce!" I bellers, steppin' over to him, "A guy drivin' a can like yours should be prepared for anything, and they ain't nobody in the world goin' to run me down and get away with it. Put up your hands, you big stiff!"
These are the earliest two matches in Google Books search results, although the expression is quite common by the mid-1920s, it's euphemistic qualities making it a favorite choice in periodicals such as Boys' Life.
Best Answer
Fully Qualified means that whatever it is has all the qualifications which are applicable. This could mean a qualification such as an FQDN has:
That is, a fully-qualified domain name is limited to a specific domain, and that limitation in scope is sufficiently stringent to make it unambiguous.
But they could be academic or vocational qualifications:
In these cases one would not talk of an "unambiguous carpenter".