Arrange the following in the ascending order of wavelength $(\lambda)$ : (A) Microwaves $\left(\lambda_1\right)$ (B) Ultraviolet rays $\left(\lambda_2\right)$ (C) Infrared rays $\left(\lambda_3\right)$ (D) X-rays $\left(\lambda_4\right)$ Choose the most appropriate answer from the options given below :

• A

  $\lambda_4 \lt \lambda_3 \lt \lambda_2 \lt \lambda_1$
• B

  $\lambda_3 \lt \lambda_4 \lt \lambda_2 \lt \lambda_1$
• C

  $\lambda_4 \lt \lambda_3 \lt \lambda_1 \lt \lambda_2$
• Correct answer
  D

  $\lambda_4 \lt \lambda_2 \lt \lambda_3 \lt \lambda_1$

Hence, the correct answer is option: 'D'.