The positions of three elements A, B and C in the periodic table are shown below:
`{:("Group 16","Group 17"),(-,-),(-,A),(-,-),(B,C):}`
State whether C is more reactive or less reactive than A.

Explanation

To determine whether element C is more reactive or less reactive than element A, we need to analyze their positions in the periodic table and understand the trends in reactivity for non-metals.

### Step-by-Step Solution:

1. **Identify the Groups**:
- Element A is in Group 17 (the halogens).
- Element C is also in Group 17 (the halogens).
- Element B is in Group 16.
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