 
 <translate> 7a/30 tells us that a is a factor of 30, which has 2, 3, and 5 as its prime factors. Each of them is distinct. Moreover, all multiples of 30 less than 200 can be derived by multiplying these prime factors alone. Thus, number of different prime factors is 3.
Thus, the answer is (B). <hau> 7a/30 ya gaya mana cewa a wani abu ne na 30, wanda yake da 2, 3, da 5 a matsayin manyan abubuwan da suke raba shi. Kowannensu ya bambanta. Bugu da ƙari, duk nau'ikan 30 ƙasa da 200 za'a iya samo su ta hanyar ninka waɗannan mahimman abubuwan kawai. Saboda haka, yawan masu rarraba firamare daban-daban shine 3. Saboda haka, amsar ita ce (B). 