Statement-I : In Rutherford's gold foil experiment, very few `alpha`-particles are deflected back.
Because
Statement-II : Nucleus present inside the atom is heavy.

Options

A. Statement-I is true, Statement-II is true , Statement-II is correct explanation for Statement-I.
B. Statement-I is true, Statement-II is true , Statement-II is NOT a correct explanation for statement-I
C. Statement-I is true, Statement-II is false
D. Statement-I is false, Statement-II is true

Answer

To analyze the statements given in the question, we can break down the reasoning step by step.

### Step 1: Understand Rutherford's Gold Foil Experiment
Rutherford's gold foil experiment was designed to probe the structure of the atom. In this experiment, alpha particles (which are positively charged) were directed at a thin foil of gold. Most of the alpha particles passed through the foil without any deflection, while a small fraction were deflected back.

**Hint:** Consider what the experiment was designed to reveal about the atomic structure.

### Step 2: Analyze Statement-I
Statement-I states that "In Rutherford's gold foil experiment, very few alpha particles are deflected back." This is indeed true. The majority of the alpha particles passed through the foil without any interaction.

**Hint:** Think about the implications of most particles passing through without deflection.

### Step 3: Analyze Statement-II
Statement-II claims that "The nucleus present inside the atom is heavy." This statement is also true. The nucleus, which contains protons and neutrons, is dense and contains most of the atom's mass.

**Hint:** Reflect on the composition of the nucleus and its significance in the atom.

### Step 4: Correlate the Statements
While both statements are correct, we need to determine if Statement-II provides a valid explanation for Statement-I. The reason why very few alpha particles are deflected is not solely because the nucleus is heavy. Instead, it is primarily due to the fact that most of the atom is empty space. When alpha particles encounter the nucleus, they may be deflected, but since the nucleus occupies a very small volume compared to the entire atom, most particles pass through without hitting it.

**Hint:** Consider the spatial distribution of the nucleus relative to the entire atom.

### Step 5: Conclusion
Thus, while both statements are true, Statement-II does not correctly explain Statement-I. Therefore, the answer to the question is that both statements are correct, but Statement-II is not the correct explanation for Statement-I.

### Final Answer:
Both Statement-I and Statement-II are correct, but Statement-II is not the correct explanation for Statement-I.

---