The output below is from Rguroo. Suppose you wish to perform the backward selection method of stepwise regression to choose an appropriate model for Calories. Which of the explanatory variables (if any) should you eliminate first? Regression Coefficients Estimates and t-Test Model formula: Calories ~ Age + Smoke + Fat + Fiber + Cholesterol + BetaDiet + RetinolDiet + Sex Reference Level(s): Smoke (No), Sex (Female) Term Coefficient Estimate Standard Error t Value Pr > |t| (P-Value) (Intercept) 284.285 83.8214 3.39155 0.000786282 Age -3.17975 1.21652 -2.6138 0.00939682 Smoke (Yes) 80.0956 48.7941 1.6415 0.101721 Fat 14.2529 0.716769 19.8849 4.6125e-57 Fiber 32.046 3.66255 8.74966 1.46409e-16 Cholesterol 0.432289 0.183813 2.35178 0.0193174 BetaDiet 0.0092525 0.0126773 0.72985 0.46604 RetinolDiet 0.0170222 0.031599 0.538694 0.59049 Sex (Male) 104.324 52.3714 1.99201 0.0472584 Smoke Fiber Fat Sex Cholesterol Age BetaDiet No explanatory variables should be removed. RetinolDiet