The question in the image asks about the real part of the complex number $z = -\sqrt{3}i$.

A complex number is typically written in the form $z = a + bi$, where $a$ is the real part and $b$ is the imaginary part. In this case, $z = -\sqrt{3}i$ can be rewritten as $z = 0 + (-\sqrt{3})i$.

Therefore, the real part of $z$ is 0.

The correct answer is d. 0.

Would you like any more details on this concept, or have any questions? Here are 5 related questions to deepen your understanding:

1. What is the imaginary part of a complex number, and how is it identified?
2. How do you graph complex numbers on the complex plane?
3. What is the modulus of the complex number $z = -\sqrt{3}i$?
4. Can you add two complex numbers? How would you add $1 + 2i$ and $3 - 4i$?
5. How do you multiply two complex numbers, such as $(2 + 3i) \times (1 - i)$?

Tip: Always remember that the real part of a complex number corresponds to the term without the $i$, while the imaginary part is the coefficient of $i$.