Puzzling verbal analogy

With 'stem' I assume they mean word stem: silkworm and honeybee.

Personally I'd prefer D on the basis that the silk is to protect the silkworms young in the way an egg protects the growing chicken, but I'd have lost. Sometimes you just need to know what the examiner wants..

Perhaps it is because silk is a product of the worm, honey is the product of a bee, but an egg is in a different category.

In one sense, eggs are the products of chickens. In another sense, eggs when hatched produce chickens. The producer/ product distinction is not as clear as the worm and bee examples. Eggs are embryonic chickens, so they are just chickens in a different form.

There is another distinction: offspring are qualitatively different from non-living products. Eggs are offspring, so the term reproduction is more apt than product.

Typically analogies are looking for the answer that is both correct and is most closely related to the stem (which is the set of two words you are given between which you're to find the relationship). In this case, A makes the most sense because only one type of worm makes silk (i.e. a silkworm) just as only one type of bee makes honey (i.e. the honeybee). Numerous breeds of chickens can produce eggs, so that wouldn't be the logical choice - though I could absolutely see that question tripping me up as well!

When you look at an analogy, first determine the relationship then try both phrases in a sentence, only changing the key words. For example, "Silk is made by a silkworm" and "Honey is made by a honeybee." Looking at it that way, I think it's easier to see why you wouldn't say, "Egg is made by an eggchicken."

I hope this helped clarify things a bit. Best of luck to you on your studies!

To answer your aside, "stem" is a technical term used by test writers for the part of a question that precedes the options.

A multiple choice item consists of a problem, known as the stem, and a list of suggested solutions, known as alternatives.

source (Vanderbilt University website)

(I agree with TotsieMae about your main question.)