Answer :

To determine which expressions are equivalent to [tex]\(3(-2a - 4) + 3a\)[/tex], let's go through a detailed, step-by-step process of simplifying the given expression and comparing it to each of the options.

### Step 1: Simplify the given expression
Let's start by simplifying the expression [tex]\(3(-2a - 4) + 3a\)[/tex]:

1. Distribute the 3:
[tex]\[ 3(-2a - 4) + 3a = 3 \cdot (-2a) + 3 \cdot (-4) + 3a \][/tex]

2. Simplify each term:
[tex]\[ 3 \cdot (-2a) = -6a \][/tex]
[tex]\[ 3 \cdot (-4) = -12 \][/tex]

Now, substitute these back into the expression:
[tex]\[ -6a - 12 + 3a \][/tex]

3. Combine like terms:
[tex]\[ -6a + 3a - 12 \][/tex]
[tex]\[ (-6a + 3a) - 12 = -3a - 12 \][/tex]

Thus, the simplified form of the expression [tex]\(3(-2a - 4) + 3a\)[/tex] is:
[tex]\[ -3a - 12 \][/tex]

### Step 2: Compare with each option
Now we will compare the simplified expression [tex]\(-3a - 12\)[/tex] to each of the given options:

- Option A: [tex]\(-6a - 12 + 3a\)[/tex]

Simplify Option A:
[tex]\[ -6a - 12 + 3a = (-6a + 3a) - 12 = -3a - 12 \][/tex]

This is exactly [tex]\(-3a - 12\)[/tex], which matches our simplified expression.

- Option B: [tex]\(3a + 12\)[/tex]

[tex]\(3a + 12\)[/tex] is not equivalent to [tex]\(-3a - 12\)[/tex]. The signs and terms do not match, so this expression is incorrect.

### Conclusion
Based on the above steps:

- Option A [tex]\(-6a - 12 + 3a\)[/tex] simplifies to [tex]\(-3a - 12\)[/tex] and is equivalent to the given expression.
- Option B [tex]\(3a + 12\)[/tex] does not match [tex]\(-3a - 12\)[/tex].

So, the correct answer is:
A. [tex]\(-6a - 12 + 3a\)[/tex]