Hello,
5355 is divisble by 3 since 5+3+5+5=18 is divisible by 3
5355=3*1785
1785 is divisble by 3 since 1+7+8+5=21 is divisible by 3
1785=3*595
595 is not divisible by 3 but by 5
595=5*119
119 is divisible by 7 since 1*2+1*3+9*1=14 is divisible by 7.
119=7*17
17 is prime
Answer A