Read the following passage and choose the letter A, B, C or D to indicate the correct answer to each of the questions from 35 to 42.

In the USA, the UK and many other countries, a lot of babies were born in the “baby boom” of the late 1940s and 1950s; after that the birth-rate fell. Baby boomers have now retired, or are approaching retirement, and this is causing headaches for many organizations: there are not enough people to succeed their top managers when they retire.

Does your organization have key staff who can’t easily be replaced? A CEO or financial director, perhaps, or a technical expert with knowledge that nobody else in the organization has. If your answer is “yes”, what will happen when they retire, or leave for another company? Will you wait until the last moment before looking for someone to replace them? Or is your organization thinking about likely future changes now, as it should be, and making plans, so that there is likely to be someone ready to replace the person leaving? If the answer is that you are planning ahead, your organization is carrying out succession planning.

Succession planning means looking inside the organization for “high-fliers” - current staff members with the potential to fill key positions - and planning the training, responsibilities and promotion they need, to make them ready when a senior vacancy occurs - which may not be for several years. The company benefits by being able to make an internal promotion when a key person leaves, and in the meantime it benefits by developing the skills of its high-fliers and encouraging them to stay. And the high-fliers benefit, because they achieve their full potential, a career is planned for them within the organization, and they can look forward to a senior post in time.

The training program planned for the high-fliers will help them to develop the leadership skills they need for more senior roles, skills such as planning long-term strategies. A career path is also planned, so that each high-flier moves into a number of different positions over a few years, to gain the experience and know ledge they need.

Sometimes a staff member is chosen as a potential successor to a particular senior manager, but a better method is for organizations to select a number of high-fliers, and prepare them for a range of senior roles. An organization can’t be certain when a particular senior manager will leave. Having a group of people being prepared fee top positions makes it easier to replace someone who leaves unexpectedly, and also means that there are other people available if a high-flier leaves the company.

Which of the following can best replace the word “senior” the passage?

I found it very hard to _____ between the two sounds.