Answer
$(2a+b)^{3}$
Work Step by Step
We need to factor:
$8a^{3}+12a^{2}b+6ab^{2}+b^{3}$
We rewrite this as:
$(2a)^3+3(2a)^2b^1+3(2a)2b^2+b^3$
We notice that this corresponds to an expanded binomial with a power of $3$ and terms $2a$ and $b$:
$(2a+b)^{3}$