How many are the incorrect statements from the followings:
a) In museum insects are preserved in insect boxes after collecting and killing.
b) Monkey, gorilla and gibbon are placed in class mammalia.
c) In an order similar characters are more as compared to different genera included in a family.
d) Three pairs of jointed legs are present in all chordates.

Options

A. Two
B. Three
C. One
D. Four

Answer

To determine how many statements are incorrect from the provided options, let's analyze each statement step by step.

### Step 1: Analyze Statement A
**Statement A:** "In museum insects are preserved in insect boxes after collecting and killing."
- This statement is **correct**. Insects are indeed collected, killed, and then preserved in insect boxes for study and identification in museums.

### Step 2: Analyze Statement B
**Statement B:** "Monkey, gorilla and gibbon are placed in class Mammalia."
- This statement is also **correct**. All three organisms—monkey, gorilla, and gibbon—are mammals and are classified under the class Mammalia.

### Step 3: Analyze Statement C
**Statement C:** "In an order similar characters are more as compared to different genera included in a family."
- This statement is **incorrect**. In biological classification, as we move from species to higher taxonomic ranks (like genus, family, and order), the number of shared characteristics decreases. Therefore, the statement that organisms in an order share more similar characters than those in a family is false.

### Step 4: Analyze Statement D
**Statement D:** "Three pairs of jointed legs are present in all chordates."
- This statement is **incorrect**. Chordates do not have three pairs of jointed legs. This characteristic is typical of arthropods, not chordates. Chordates are defined by the presence of a notochord, and they do not necessarily have jointed legs.

### Conclusion
After analyzing all four statements:
- **Statement A:** Correct
- **Statement B:** Correct
- **Statement C:** Incorrect
- **Statement D:** Incorrect

Thus, there are **2 incorrect statements** (C and D).

### Final Answer
The number of incorrect statements is **2**.

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