Autumnal leaf colour is due to

Options

A. Chlorophyll a
B. Carotenoids
C. Anthocyanins
D. Betacyanin.

Answer

**Step-by-Step Solution:**

1. **Understanding Autumnal Leaf Color**: Autumnal leaf color refers to the change in color of leaves during the autumn season. This change is primarily due to the breakdown of chlorophyll and the presence of other pigments.

2. **Identifying the Pigments**: The main pigments involved in leaf color are chlorophyll, carotenoids, anthocyanins, and beta-cyanins. Each of these pigments has different roles and colors.

3. **Role of Chlorophyll**: Chlorophyll is the pigment responsible for the green color in leaves. During autumn, chlorophyll breaks down, leading to the exposure of other pigments.

4. **Carotenoids**: Carotenoids are pigments that can appear yellow or orange. They are present in leaves but are usually masked by the green chlorophyll. When chlorophyll breaks down in autumn, carotenoids become more visible, giving leaves their autumn colors.

5. **Conclusion**: The autumnal leaf color is primarily due to carotenoids, which are responsible for the yellow and orange hues seen in many deciduous trees during this season.

**Final Answer**: Autumnal leaf color is due to carotenoids.

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