Read the excerpt from the strange case of dr. jekyll and mr. hyde.

and the next moment, in a voice that was already fairly well under control, "have you a graduated glass? ” he [hyde] asked.

i rose from my place with something of an effort and gave him what he asked.

he me with a smiling nod, measured out a few minims of the red tincture and added one of the powders. the mixture, which was at first of a reddish hue, began, in proportion as the crystals melted, to brighten in colour, to effervesce audibly, and to throw off small fumes of vapour. suddenly and at the same moment, the ebullition ceased and the compound changed to a dark purple, which faded again more slowly to a watery green. my visitor, who had watched these metamorphoses with a keen eye, smiled, set down the glass upon the table, and then turned and looked upon me with an air of scrutiny.

which is the best summary of the events described?

a. hyde asks for a glass. lanyon gives it to him, and hyde creates a mixture in it. after the mixture stops transforming, hyde sets down the glass and looks critically at lanyon.
b. hyde gives a glass to lanyon and him make a mixture that transforms several times before settling to a stop. then hyde sets the glass down on the table and smiles.
c. hyde asks for a glass, and with great effort, lanyon gets one for him. then they both create a mixture in the glass that rapidly transforms, changing from red to purple to green in a few seconds.
d. hyde hands a glass over to lanyon, who wants to make a potion from the powders and crystals that were in the drawer. the compound changes colors several times before stopping.