Show that $\mathbb{E}[Tr(X)]=Tr(E[X])$

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Let $X$ be a $p\times p$ random matrix. Show that $$\mathbb{E}[Tr(X)]=Tr(E[X])$$

My solution:

$$\mathbb{E}[Tr(X)]=\mathbb{E}[\sum^p_{i=1}x_{ii}]$$

And by linearity of expectation, the RHS is equal to

$$\sum^p_{i=1}\mathbb{E}[x_{ii}]=Tr(\mathbb{E}[X])$$

Is my solution correct?