Procedure to find propositional formula given by the tree

Question

The propositional formula given by the tree:

1. $\land \lor x_2 \lor x_1 \lnot x_1 \lnot x_1$
2. $(x_2\lor x_2)\land (x_1\lor x_1)$
3. $(\lnot x_1 \lor x_2)\land (\lnot x_1 \lor x_2)$
4. None of these

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My attempt :

I googled and I guessed this should be option $(3)\space (\lnot x_1 \lor x_2)\land (\lnot x_1 \lor x_2)$

My question is :

$x_1$ should be right child of $\lnot$ in both subtree?

Can you explain it, please?

Answer 1

(Lifting my comment into an answer.)

$\neg$ is a unary operator, and hence does not have "left" and "right" children in a propositional tree. It just has a single child.