Select the correct option for the following matches:

$(1)$ Gram-positive bacteria	$(a)$ Thermoacidophiles
$(2)$ Bacteria living in acidic medium	$(b)$ Firmicutes
$(3)$ Gram-negative bacteria	$(c)$ Halophiles
$(4)$ Bacteria living in extreme salty conditions	$(d)$ Spirochetes

• A
  $(1-d), (2-c), (3-b), (4-a)$
• B
  $(1-a), (2-c), (3-b), (4-d)$
• C
  $(1-c), (2-d), (3-a), (4-b)$
• D
  $(1-b), (2-a), (3-d), (4-c)$