3）企业在对市场营销渠道的设计和构建时，一方面，应考虑选择合理的营销渠道，另一方面，还应选择同实力雄厚、信誉度高的企业进行合作，建立长期稳固的分销合作关系。
选项：

A:When designing and constructing marketing channels, on the one hand, enterprises should consider choosing reasonable marketing channels, on the other hand, they should also choose to cooperate with enterprises with strong strength and high credibility to establish long-term and stable distribution cooperation relationship.
B:When designing and building marketing channels, enterprises should considering choosing appropriate channels. On the other hand, they should choose to establish long-term and stable distribution partnership with powerful and credible companies.
C:When designing and constructing marketing channels, enterprises should consider choosing reasonable marketing channels. On the other hand, they should also choose to cooperate with enterprises with strong strength and high credibility to establish long-term stable distribution cooperation.
D:When designing and constructing marketing channels, enterprises should, on the one hand, consider choosing reasonable marketing channels; on the other hand, they should also choose to cooperate with enterprises with strong strength and high credibility to establish long-term and stable distribution cooperation relations.