If $$9a^2 + 4b^2 + 49c^2 + 18 = 2(2b + 28x - 3a)$$, then the value of $$(a + 2b - c)$$ will be:

A

$$\frac{11}{21}$$

B

$$\frac{2}{21}$$

C

$$\frac{26}{21}$$

D

$$\frac{5}{21}$$