Answer: D. .400
Step-by-step explanation:
Given : In a multiple regression model involving 44 observations, the following estimated regression equation was obtained.

For this model,
Regression sum of squares =SSR = 600
and Sum of squares due to error =SSE = 400.
Total sum of squares = SST= SSR+SSE
SST= 600+400=1000
The multiple coefficient of determination is given by :-

Substitute values , we get


Thus, the multiple coefficient of determination for the above model is 
Hence, the correct answer is D. .400.