Let `R` be a relation from a set `A\ to` a set B, then `R=AuuB` b. `R=AnnB` c. `RsubeAxxB` d. `RsubeBxxA`

Explanation

To solve the question, we need to understand the definition of a relation between two sets. A relation from set A to set B is defined as a subset of the Cartesian product of A and B.

### Step-by-Step Solution:

1. **Understanding the Relation**: A relation \( R \) from set \( A \) to set \( B \) is defined as a subset of the Cartesian product \( A \times B \). The Cartesian product \( A \times B \) consists of all ordered pairs \( (a, b) \) where \( a \in A \) and \( b \in B \).

2. **Identifying the Options**: We have four options to analyze:
- a. \( R = A \cup B \)
...