Add -ence or -ance to the following word. Double the r when necessary.

deter

i think the answer is c.  

  plan: i will begin with a quotation about the importance of unity in a community. then, i will state my claim that an activity will unite our school by creating a shared vision, purpose, and direction. in the body, i will use three main points that describe the different avenues the students can take: through a variety of clubs, through a special event, or through an awareness week. i will provide evidence about other towns that have unity activities and the kinds of events that they include. pictures will illustrate my three main points in action. for the ending, i will restate the main idea in a new way and pose a question to keep the audience thinking. 

the best practice

1. keep your workspace clean

2. wash your hands

3. seperate and clean chemicals and equipment

4.   use microfiber cleaning utensils

5. clean and sanitize all work surfaces

hope this !