Which statement correctly defines the imaginary unit $i$ and its basic square property?

Compute $2i(3-4i)$ and express the result in standard form $a+bi$.

What is the complex conjugate of $-3+7i$?

Rationalize and simplify $\frac{3}{2-5i}$, and express the result in standard form $a+bi$ in lowest terms.

Find $i^{1000}$ using the fastest method.