D. succor
Succor is assistance or help. In the sentence, Josiah is hoping that the medication would not only bring down his fever but also lessen his symptoms so that he was not uncomfortable.
A requisite is a requirement. Often this word is seen attached to the prefix pre-, as in prerequisite. Classes that are prerequisites must be taken before a student is allowed to take a higher more difficult course. The prerequisite class often contains the building blocks the next level course relies on for understanding of the material.
Symmetry is being the same on either side. Pictures and images are better if they have a sense of symmetry. The amount of visual content on one half of the image is the same as on the other half of the screen.
Machination is a plot or scheme. The terrorists machinations to end the cruel regime were thwarted when his sister reported him to local authorities.
