The correct answer is (C).
In this question there are two rows of symbols and a missing operator. The operator changes the order of the symbols that appear in the upper row to a new order in the lower row.
The digits of the operator represent the symbol according to its position in the upper row before it was changed by the operator. In order to solve this question, you should look at the first symbol of the lower row.
Search the position of that symbol in the upper row. This position is the first digit of the operator.
In this example, a triangle is the first symbol on the lower row. Its position in the upper row is second, so the first digit is 2.
You can now mark answer 2341 because it's the only answer that starts with the digit 2.
In case you can’t rule out the other alternatives, you will continue by checking the second symbol in the lower row- a heart. Then check its position in the upper row.
Its position is third, so the second digit of the operator is 3. The third symbol is a star, its position in the upper row is fourth, so the next digit is 4.
The fourth symbol is a circle, its position in the upper row is first, so the next digit is 1.
The correct operator is 2341.