Which two month in a year have same calendar ?

January - October are two month in a year have same calender. So, Option (c) is correct.

Because those two months which have the same code have the same calendar.

Code for    

Jan – 0         Feb – 3        Mar – 3

Apr – 6        May – 1       June – 4

July – 6        Aug – 2       Sep – 5

Oct – 0         Nov – 3       Dec – 5