3 1 = 3 The last number is 3.

3 2 = 9. The last number is 9.

3 3 = 27 The last number is 7.

3 4 = 8 1 The suffix is 1.

3 5 = 243 The last number is 3.

. . . . . . . . . . . .

So the mantissa of 3 n (n is a positive integer) is a cycle of 4 numbers: 3, 9, 7, 1.

So 8n+3=2n*4+3, so the last number is 3, 9, 7, 1, and then the third one is 7.

So the mantissa of 3 (8n+3)+2 is 9.

So the remainder of this number divided by 5 is the remainder of 9 divided by 5, which is 4.

So choose e