Option C:

Solution:
Given data:
![3\left[\begin{array}{cc}-2 & 0 \\4 & 7\end{array}\right]](https://img.qammunity.org/2021/formulas/mathematics/college/vdbf8n98tradh2taf95g9euepyuxsiwsn7.png)
To find the product:
Scalar element = 3
Scalar multiplication:
Multiply each of the matrix element by a scalar.
Here multiply each of the matrix element by 3.

Simplifying each element, we get

The value of the given matrix is
.
Option C is the correct answer.