IMO : C
Statement 1 :
K is divisible by 4
K can be 4,8,12,16 etc,may or may not be a perfect square.
Insufficient.
Statement 2 :
K is divisible by exactly 4 different primes
picking Numbers
210 is divisible by 2,3,5,7 but not a perfect square
44100 is divisible by 2,3,5,7 and is a perfect square.
Hence Insufficient.
Combining 1 and 2
If the number is dicisible by 4 different primes and is divisible by 4 it will be perfect square.
Eg : 44100
or
13*13*2*2*5*5*7*7 is divisible by 4 and a perfect square.
Similarly other numbers.
Whats the OA?