Final answer:
The phrase translates to the equation 53 + 4B = 21, corresponding to linear algebra.
Step-by-step explanation:
The phrase "fifty-three pulse four times B is as much as twenty-one" translates into an equation by equating the sum of fifty-three and four times a variable B to the value twenty-one. The correct translation to this phrase would be the mathematical equation 53 + 4B = 21. This matches the format of conventional linear equations, which is an integral part of algebra in mathematics.