The response of an effector is
to maintain homeostasis
to decrease the external stimulus
to transmit a negative feedback impulse
to provide a counter stimulus to neurons

To maintain homeostasis

Explanation:

Effectors are organs, cells or tissues that provides the required output after receiving a feedback from the control center. Nerve impulse instructs the effector to bring things into balance and required range. They then influence the magnitude of stimulus and maintain homeostasis.

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