The expression is :
Since,
TERMS : Terms are single numbers, variables, or the product of a number and variable.
eg : 5,9a,y
FACTOR : A factor is one part of a product.
For eg : 8x, factor are 8 and x
COEFFICIENT : A coefficient is a number multiplied by a variable
For eg : 14+c here coefficient is 14
In teh given expression 4 is multiply by the (-2), i.e 4 is the factor of the product 4 multiply by (-2).
Answer : 4 is the factor.