A group of adults, highly succeeded in their jobs, went to visit their old professor. Soon they began to _   _ the stress in work and life.

The professor went to the kitchen and returned_   _a pot（壶） of coffee and all kinds of cups — crystal (水晶的), glass, plastic; some nice looking, some common looking; some_   _, some cheap. And he told them to help _   _ to the coffee.

When all the students had a cup of coffee in hand, the professor said, “I’ve noticed that all the nice looking expensive cups were_   _， leaving behind the common and cheap ones. While it is_   _for you to take only the best for yourselves, that is the root(根源) of your _   _ and stress.

You know that the cup itself adds no quality (质量) to the coffee, _   _you really wanted was coffee, not the cup, _   _ you consciously went for the best cups.

Now consider this: Life is the coffee. The jobs, _   _ and position in society are the cups. They are just _   _to hold life, and the type of cup does not change the quality of our life. Sometimes, by only paying attention _   _the cup, we fail to enjoy the coffee that God has _   _us. God offers us the coffee, not the cups. Please enjoy your coffee!”

The happiest people don’t have the best of everything. They just make _   _of everything.

Live simply. Love generously. Care deeply. Speak _   _. And leave the rest to God.

A公司中标某市城区高架路工程第二标段。本工程包括高架桥梁、地面辅道及其他附属工程：工程采用工程量清单计价，并在清单中列出了措施项目；双方签订了建设工程施工合同，其中约定工程款支付方式为按月计量支付，并约定发生争议时向工程所在地仲裁委员会申请仲裁。
对清单中某措施项目，A公司报价100万元。施工中，由于该措施项目实际发生费用为180万元，A公司拟向业主提出索赔。
业主推荐B公司分包钻孔灌注桩工程，A公司审查了B公司的资质后，与月公司签订了工程分包合同。在施工过程中，由于月公司操作人员违章作业，损坏通信光缆，造成大范围通信中断，A公司为此支付了50万元补偿款。
A公司为了应对地方材料可能涨价的风险，中标后即与某石料厂签订了价值400万元的道路基层碎石料的采购合同，约定了交货日期及违约责任(规定违约金为合同价款的5%)并交付了50万元定金。到了交货期，对方以价格上涨为由提出中止合同，A公司认为对方违约，计划提出索赔。
施工过程中，经业主同意，为保护既有地下管线，增加了部分工作内容而原清单中没有相同项目。
工程竣工，保修期满后，业主无故拖欠A公司工程款，经多次催要无果。A公司计划对业主提起诉讼。
问题：

对业主拖欠工程款的行为，A公司可以对业主提起诉讼吗说明原因。如果业主拒绝支付工程款，A公司应如何通过法律途径解决本工程拖欠款问题