Answer:
A. Iambic Pentameter.
Step-by-step explanation:
Iambic pentameter is a meter of writing poetry or verse drama that has five metrical feet. This five metrical feel refers to the use of five stressed syllables followed by five unstressed syllables.
In the given lines from Act, I scene iv of William Shakespeare's "Macbeth", the meter used is iambic pentameter. In these lines, Macbeth is talking about how he needs to 'overstep' the Prince of Cumberland (Malcolm) in order to become the king of Scotland as predicted by the three witches.
Thus, the correct answer is option A.