Steps I and VII Come Together to Complete the Carbon-Silicate

Multiple Choice

Steps I and VII come together to complete the carbon-silicate cycle. However, two consecutive steps of this cycle are OUT OF ORDER - which two?
I. In weathering, atmospheric CO2 dissolves in rainwater to form carbonic acid
(H2C03)
II. Carbonic acid dissociates to form hydrogen ions (H+) as rainwater moves through soil
III. Hydrogen ions enter silicate-rich minerals such as feldspar, releasing calcium ions (Ca2+)
IV. Microscopic marine organisms incorporate (Ca2+) and HC03-) into their shells
V. Calcium and bicarbonate ions wash into surface waters and eventually reach the ocean
VI. Shells are incorporated into sedimentary rock
VII. Geological uplift exposes limestone, which is eroded by weathering returning C02 to the atmosphere and water.

A) II and III
B) III and IV
C) IV and V
D) V and VI
E) none, all the steps are in the correct order