Consider the following statements:
$(1)$ Joule-Thomson experiment is isoenthalpic as well as adiabatic.
$(2)$ $A$ negative value of $\mu_{JT}$ (Joule-Thomson coefficient) corresponds to warming of a gas on expansion.
$(3)$ The temperature at which neither cooling nor heating effect is observed is known as inversion temperature.
Which of the above statements are correct?

• A
  $1$ and $2$
• B
  $1$ and $3$
• C
  $2$ and $3$
• D
  $1$,$2$ and $3$