Fill in the blanks in the passage with the most appropriate words from the given options: We all have a ___ (1) ___ in the infrastructure surrounding ...

Fill in the blanks in the passage with the most appropriate words from the given options:

We all have a ___ (1) ___ in the infrastructure surrounding us - the roads, buildings, power lines, and telephone networks that we ___ (2) ___ daily. How well they are built and operated is ___ (3) ___ to economic growth and is a key arbiter of an economy's competitiveness - and yet, virtually every economy faces an array of infrastructure challenges. Just a few examples illustrate some of the pressing issues. South Africa's power distribution network has an estimated maintenance backlog of $4 billion - equivalent to half of the country's total investment in electronic power generation and distribution in 2011. The U.S. Department of Transportation estimates that 15% of the country's roads are in an unacceptable condition and says that road congestion costs the US an estimated $100 billion per year. Just to keep ___ (4) ___ with anticipated global GDP growth, the world needs to spend $57 trillion, or on average $3.2 trillion a year, on infrastructure over the next 18 years. That is more than the entire worldwide stock of infrastructure on the ground today - and nearly 60% more than the world has invested over the past 18 years. Tackling maintenance backlogs, future-proofing infrastructure to cope with climate change and ___ (5) ___ development goals such as access to clean water and all-weather roads to transport goods to markets would cost a great deal. The bill for all of that looks prohibitive at a time when many governments are highly indebted and capital is tight. A focus on both, the huge need for additional investment and potential difficulties in financing it, ___ (6) ___ the debate. Pessimism rules, but it needn't be that way. There are ways of cutting the bill down to size and dealing with the challenge. The answer ___ (7) ___ in improving the way we plan, build and operate infrastructure - in other words, we need to boost its productivity.