<span>C)
It suggests that the author is hopeful about and believes that the
thermometer pill will help reduce athlete deaths due to heatstroke. </span>
C) It suggests that the author is hopeful about and believes that the thermometer pill will help reduce athlete deaths due to heatstroke.
The adjective <em>promising </em>means that something exhibits signs of future success. As a consequence, the writer is confident that the thermometer pill will be favorable, has potential and is full of promise that athletes will be highly benefited by them.