Answer: option b
Explanation:
Our task is to find the expression in which x has a coefficient of 1.
The coefficient of a variable is the number before the variable. For example, in 3x, the coefficient is 3.
Let's take a look at each of these expressions.
x² + 3x + 4 -> the coefficient of 'x' is 3.
3x² + x - 8 -> the coefficient of 'x' is 1.
2x² - x + 1 -> the coefficient of 'x' is -1.
2x² - 2x - 1 -> the coefficient of 'x' is -2.
∴ The answer is option b.