GATE CSE 2023 Q40: Language accepted by empty stack by a three-state PDA

Consider the pushdown automaton (PDA) $P$ below, which runs on the input alphabet $\{a, b\}$, has stack alphabet $\{\perp, A\}$, and has three states $\{s, p, q\}$, with $s$ being the start state. A transition from state $u$ to state $v$, labelled $c/X/\gamma$, where $c$ is an input symbol or $\epsilon$, $X$ is a stack symbol, and $\gamma$ is a string of stack symbols, represents the fact that in state $u$, the PDA can read $c$ from the input, with $X$ on the top of its stack, pop $X$ from the stack, push in the string $\gamma$ on the stack, and go to state $v$. In the initial configuration, the stack has only the symbol $\perp$ in it. The PDA accepts by empty stack.