The pieces in Figure (X) are put together, without overlapping, to make one of the figures given in the options. Which one? (Lines inside an option show its pieces.)

Answer & explanation
Correct answer: option 3
The correct answer is Option (3) →

A figure can be formed from the pieces only if it is cut into exactly the 4 pieces of Figure (X), each with the same shape and size (a piece may be turned round). The 4 pieces of Figure (X), turned round where needed, fit together as the house shape of Option (3), as shown in the same colours below.

Option (1) — Incorrect. The line between its bottom piece and its bottom-left piece is in a different place: the bottom piece has one small square less and the bottom-left piece one small square more, so neither of them is one of the given pieces.
Option (2) — Incorrect. It is cut differently: its bottom, bottom-left, left and right pieces do not match any piece of Figure (X), even when turned round.
Option (4) — Incorrect. The line between its right piece and its bottom piece is in a different place: the right piece has one small square less and the bottom piece one small square more, so neither of them is one of the given pieces.