Final answer:
The function y = cos(x) will have multiple x-intercepts, maxima, and minima between 0 and 21 because it has a period of 2π and crosses the x-axis every π radians. Therefore, the correct answer to the question is C) Multiple x-intercepts and extrema.
Step-by-step explanation:
The function y = cos(x) is a well-known trigonometric function. As we analyze this function within the interval from 0 to 21, we can determine that it will have multiple x-intercepts and extrema (maxima and minima). The function cos(x) has an x-intercept every π radians (180 degrees), so between 0 and 21, which is slightly less than 7π, there will be several points where the cos(x) curve will cross the x-axis. The maximum points for cos(x) occur at even multiples of π, and the minimum points occur at odd multiples of π. Since cos(x) has a period of 2π, within the given range (0 to 21), there will be multiple maxima and minima. Specifically, the maxima will be at 0, 2π, 4π, and 6π, while the minima will occur at π, 3π, and 5π. Based on this analysis, the correct answer to the question 'What are the x-intercepts, maxima, and minima of y = cos(x) from 0 to 21?' would be C) Multiple x-intercepts and extrema.