To Examine the Differences Between Salaries of Male and Female

To examine the differences between salaries of male and female middle managers of a large bank, 90 individuals were randomly selected, and two models were created with the following variables considered: Salary = the monthly salary (excluding fringe benefits and bonuses) ,
Educ = the number of years of education,
Exper = the number of months of experience,
Train = the number of weeks of training,
Gender = the gender of an individual; 1 for males, and 0 for females.
Excel partial outputs corresponding to these models are available and shown below.
Model A: Salary = β₀ + β₁Educ + β₂Exper + β₃Train + β₄Gender + ε Model B: Salary = β₀ + β₁Educ + β₂Exper + β₃Gender + ε The variable Train is deleted from Model A which results in Model B. Which of the following justifies this choice?

A) The adjusted R² Model B is lower than the adjusted R² of Model A, and the variable is individually significant in Model A.
B) The adjusted R² of Model B is higher than the adjusted R² of Model A, and the variable is individually significant in Model A.
C) The adjusted R² of Model B is lower than the adjusted R² of Model A, and the variable is not individually significant in Model A.
D) The adjusted R² of Model B is higher than the adjusted R² of Model A, and the variable is not individually significant in Model A.