To simplify the expression \( a + b + c(d + 2) \), you can use the distributive property.
Starting with:
\[ a + b + c(d + 2) \]
Distributing the \( c \) results in:
\[ a + b + cd + 2c \]
So, the expression is equivalent to:
\[ a + b + cd + 2c \]
From the provided options, the correct response is:
a + b + cd + 2c.
This corresponds to the first option listed in your responses.