1) Xerophytes

2) Cereals

3) Gymnosperms

4) Most dicots

Answer:2) Cereals

Explanation:Dumb-bell shaped guard cells are found in grasses. Grasses are monocotyledons and belong to the family Poaceae or Gramineae. Cereal crops such as wheat, rice, maize, barley, millet, etc. are grasses.

Also Check:

• Endosperm
• Racemose Inflorescence
• Types Of Cymose Inflorescence
• Morphology of Flowering Plants
• Sexual Reproduction in Flowering Plants
• Anatomy of Flowering Plants – Important Notes for NEET

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