Which of the following statements is true

Options

A. `phi sub {a, b, c}`
B. `phi in {a, b, c}`
C. `0 in phi`
D. `{a} in {a, b, c}`

Answer

To determine which of the given statements is true, we will analyze each statement step by step.

### Step 1: Analyze Statement 1
**Statement:** Phi is a subset of the set A, B, C.

**Explanation:**
- The empty set (Phi) is a subset of every set. This is a fundamental property of sets.
- Therefore, this statement is **true**.

### Step 2: Analyze Statement 2
**Statement:** Phi belongs to the set A, B, C.

**Explanation:**
- The statement claims that Phi (the empty set) is an element of the set A, B, C.
- However, Phi is a subset of every set but does not belong to any set as an element.
- Thus, this statement is **false**.

### Step 3: Analyze Statement 3
**Statement:** 0 belongs to Phi.

**Explanation:**
- The empty set (Phi) contains no elements, meaning it has zero elements.
- Therefore, the statement that 0 belongs to Phi is incorrect.
- This statement is **false**.

### Step 4: Analyze Statement 4
**Statement:** A belongs to the set A, B, C.

**Explanation:**
- This statement suggests that A is an element of the set {A, B, C}.
- If A is one of the elements in the set {A, B, C}, then this statement is true.
- However, if we interpret A as a set itself, then it cannot belong to the set {A, B, C} unless specifically stated.
- Thus, this statement is **false**.

### Conclusion
After analyzing all four statements, we find that only **Statement 1** is true.

### Final Answer
The true statement is: **Phi is a subset of the set A, B, C.**

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