A regression of Sales [$1,000] on Advertising [$1,000] and Market Share [96] resulted in the following output. Refer to the results and interpret the estimated slope for Advertising. Intercept 810.00 1.31 0.20 Advertising 0.25 3.13 0.00 Market Share 187.00 Select one: Q a. If Advertising decreases by $1 while holding Market Share constant. Sales are expected to increase by $0.25 0 b. If Advertising increases by $1,000 while holding Market Share constant, Sales are expected to increase by $250 {3 c. If Advertising increases by $0.25 while holding Market Share constant. Sales are expected to increase by $1,000 0 d. If Sales increases by $1,000 while holding Market Share constant. Advertising will decrease by $250