Final Answer:
The correct expression for calculating the position of the squirrel is

Step-by-step explanation:
The given expression is

In the incorrect options:
1. Option 2 has the correct values for \( a \) and \( b \) but incorrect \( c \).
2. Option 3 has the correct values for \( a \) and \( c \) but incorrect \( b \).
3. Option 4 has the correct value for \( b \) but incorrect \( a \) and \( c \).
Understanding the correct expression is essential for accurate calculations. In \( f(x) = 2x + 1 \), \( a \) represents the coefficient of the variable \( x \), \( b \) represents the constant term, and \( c \) is the constant added to the function. In this case, the squirrel's position (\( f(x) \)) is determined by doubling the value of \( x \) and adding 1. This aligns with the standard form of a linear function, where \( f(x) \) is dependent on \( x \) with a specific coefficient and constant term.