If the following interchanges are made in signs and numbers, which equation would be correct?
Interchanges:
Signs: $$\div$$ and $$—$$
Numbers: 15 and 5

A

$$4 \times 30 - 15 \div 5 + 12 = 21$$

B

$$12 \times 30 - 15 \div 5 + 4 = 37$$

C

$$4 \times 30 - 15 \div 5 + 12 = 27$$

D

$$4 \times 30 - 5 \div 15 + 14 = 21$$