Step 1: Identify Curve 1.
- The solution gas-oil ratio (\(R_s\)) increases with pressure until bubble point pressure \(P_b\).
- Beyond \(P_b\), oil is saturated, and no more gas dissolves. Thus, \(R_s\) remains constant for \(P > P_b\).
- This matches the behavior of Curve 1.
Step 2: Identify Curve 2.
- The oil viscosity decreases with increasing pressure below \(P_b\) because gas goes into solution.
- At \(P_b\), viscosity is minimum. Beyond \(P_b\), viscosity increases with pressure due to compression.
- This behavior matches Curve 2.
Step 3: Identify Curve 3.
- The oil formation volume factor (\(B_o\)) increases as more gas dissolves in oil, reaching a maximum near \(P_b\).
- Beyond \(P_b\), oil becomes slightly compressible, so \(B_o\) decreases with pressure.
- This matches Curve 3.
Step 4: Oil density check.
- Oil density does not match Curve 3's behavior. Density generally increases monotonically with pressure.
- Hence, option (D) is incorrect.
Final Answer:
\[
\boxed{\text{(A), (B), and (C)}}
\]