You wish to calculate the amount that Astrid should withdraw from her college savings fund of $$30000$ if she wishes to withdraw equal amounts at the beginning of each month for four years. The annual nominal interest rate is $6\%$ convertible annually. Find the number of payments per year.

a$.$

$4$

b$.$

$6$

c$.$

$2$

d$.$

$1$

e$.$

$12$