The Object of Production Engineering is： A: vicinity of wellbore B: Well Groups C: Well Prodction System D: Wellbore

What are the three main aspects of nonlinear problems in the analysis of wellbore stability? A: Nonlinear elasticity B: Plasticity C: Anisotropy D: Linear elasticity

From the perspective of the fluid leakoff mechanism of fracturing fluid, which kind of fluid leakoff coefficient mainly controls the effect of fracturing fluid's wall-forming property（ ）。 A: Reservoir fluid compression zone B: Fracturing fluid invasion zone C: Filter cake area D: Wellbore area