Which of the following are monoecious and dioecious organisms ?
(a) Earthworm........... , (b) Chara ...........
(c) Marchantia ................ , (d) Cockroach .............

Explanation

To determine which of the given organisms are monoecious and dioecious, we need to understand the definitions of these terms:

1. **Monoecious**: Organisms that have both male and female reproductive organs in a single body.
2. **Dioecious**: Organisms that have male and female reproductive organs in separate bodies.

Now, let's analyze each organism provided in the question:

### Step-by-Step Solution:
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