These are the easiest type of analogy questions. Find the number of the letter in the alphabet and code the letters as numbers. Now you will notice a relation between the corresponding numbers. Translate that relation to the next set of numbers and you will have the required set of letters.
AFK : EJO : : CHM : ?
We begin by coding the letters as numbers. Hence, AFK can be coded as 1 6 and 11 and EJO can be coded as 5 10 15. Thus, we see that the second set is greater than the first set by 4. CHM can be coded as 3 8 13. Adding 4 to each we get, 7 12 17. The corresponding letters are GLQ.
People, Animals and Objects:
When the analogy uses these kinds of elements, try to make a sentence with the first two parts of the analogy. That sentence would establish the relation between the two parts. For example, consider the analogy Horse : Foal :: Lion : ?. Here, we can make a sentence like Foal is the young one of a Horse. Thus, the relation between the two is older animal to baby animal. To answer the question, we need to name the baby version of a Lion which is a cub. Hence, the answer would be a Cub.
In such cases, more than one answers are possible. Hence, it is important to proceed backwards from the options. Try to find an option that when added, subtracted, multiplied or divided by the first number would give a similar result as the first pair of numbers. Express the second number in a pair as a function of the first number.
Find the number that comes in place of the question mark.
16:? :: 4:13
13 can be expressed as different functions of 4 like 1*4+9, 2*4+5, 3*4+1 etc. We see that 3x+1 would be a suitable function as it would yield values close to the numbers given. Hence, the number in the blank would be 3*16+1 = 49. Hence, option A.