A milling machine has the following two index plates supplied along with the indexing head:
Plate 1: 15, 16,17,18, 19, 20, hole circles
Plate 2: 21,23,27,29,31,33, hole circles
It is proposed to mill a spur gear of 28 teeth using simple indexing method. Which one of the following combinations of index plate and number of revolutions is correct?

A

Plate 1: 1 revolution and 9 holes in 18 hole circles

B

Plate 2: 1 revolution and 9 holes in 21 hole circles

C

Plate 2: 1 revolution and 9 holes in 33 hole circles

D

Plate 1: 1 revolution and 9 holes in 15 hole circles