What is group displacement law ? An element belonging to group 1 decay by `beta^(c-)-` emission. To which group of the periodic table the daughter element will belong ?

Explanation

### Step-by-Step Solution:

1. **Understanding Group Displacement Law**:
- The group displacement law states how the atomic number and mass number of an element change when it undergoes radioactive decay.
- For alpha decay, the atomic number decreases by 2 and the mass number decreases by 4, resulting in the daughter element being two groups to the left in the periodic table.
- For beta decay (specifically beta minus decay), the atomic number increases by 1 while the mass number remains unchanged. This means the daughter element is positioned one group to the right of the parent element in the periodic table.

2. **Identifying the Parent Element**:
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