identify the pest:

mealybugs
Aphids
Fungus gnats
Leaf hopper
Japanese beetle
Ans: Aphids.
Aphids r sap sucking, tiny, soft bodied plant lice that cause deformation in leaf growth and lack of plant vigour. There r known 5000 varieties of aphids around the world and one of the most destructive crop pests. They also transmit plant virus from one plant to another. They such the juices from leaves and stems causing discoloration, leaf curling, yellowing and stunted growth. Large scale infestation on plant can produce white sugary substance which is the aphid’s waste product known as honey dew. This attracts ants which in turn fuels fungus growth on plants. They r found in colours of yellow, white, pink, brown or even black.
How to prevent aphid growth:
Grow companion plants like marigolds, tulsi, dill, lemon grass, etc around ur plants to keep pest away.
Spray infected plants with water to dismantle them from plants. Then spray neem oil+ soap solution emulsion, garlic water, all over infected plant once a week till infestation disappears.