Compared to butane and other alkanes, there is no free rotation around any C-C bonds in cyclobutane. Provide a brief explanation.

• A. There is no free rotation around any C-C bonds in cyclobutane because they are constrained in a ring structure.
• B. There is no free rotation around any C-C bonds in cyclobutane because they are constrained by pi bonds.
• C. There is no free rotation around any C-C bonds in cyclobutane because the orbitals used are sp² hybridized.
• D. There is no free rotation around any C-C bonds in cyclobutane because the orbitals used are sp³ hybridized. 

Answer: (A)