In a certain code language,

A + B means 'A is the mother of B'

A – B means 'A is the son of B'

A x B means 'A is the daughter of B'

A ÷ B means 'A is the brother of B'

Based on the above, how is P related to T if 'P – Q ÷ R x S + T' holds?

Let me decode each relationship in the expression 'P – Q ÷ R x S + T':

Expression	Meaning
P – Q	P is the son of Q
Q ÷ R	Q is the brother of R
R x S	R is the daughter of S
S + T	S is the mother of T

---

Now, building the family tree from these relationships:

Since S is the mother of T, T is S's child.

Since R is the daughter of S, R is also S's child. This means R and T are siblings.

Since Q is the brother of R, Q is also S's child. This means Q and T are siblings (both have the same mother S).

Since P is the son of Q, P is Q's child.

---

Finding P's relation to T:

Q and T are siblings (both are children of S).

Q is T's brother (since Q is male - he's described as "brother of R").

P is Q's son.

Therefore, P is T's brother's son.

The correct answer is Option 3: Brother's son.