Consider the following statements for completely balancing a single rotating mass:

1). Another rotating mass placed diametrically opposite in the same plane balances the unbalanced mass.

2). Another rotating mass placed diametrically opposite in a parallel plane balances the unbalanced mass.

3). Two masses placed in two different parallel planes balance the unbalanced mass.

Which of the above statements is/are correct?

(a) 1 only

(b) 1 and 2

(c) 2 and 3

(d) 1 and 3 .