The correlation coefficient \( r \) measures the strength and direction of a linear relationship between two variables. In the case of the linear equation given, \( y = 43x - 4 \), this represents a perfect linear relationship.
For a perfect linear relationship:
- The correlation coefficient \( r \) is equal to 1 if the relationship is positive, and \( r \) is equal to -1 if the relationship is negative.
Since the slope of the line (43) is positive, the correlation coefficient \( r \) is:
\[ r = 1.00 \]
Thus, the correct answer from the options provided is:
1.00