The orangutan is our closest living 1. ?

Explanation

Correct Answer: relative

After an adjective, we need a noun. Relative refers to a species that is closely related.

(RELATE) among the animal species. There is just a two percent difference in our DNA and this perhaps 2. ?

Explanation

Correct Answer: accounts

The subject this requires a verb. The phrasal verb accounts for means to explain the reason for something.

(COUNT) for the number of tourists flocking to the rainforests of south-east Asia in the hope of seeing the creatures in close 3. ?

Explanation

Correct Answer: proximity

The phrase in close proximity is a common collocation meaning very near in space.

(PROXIMATE). Just glimpsing one is an 4. ?

Explanation

Correct Answer: unforgettable

An adjective is needed before the noun experience. Unforgettable means something so beautiful or shocking that you cannot forget it.

(FORGET) experience. With logging and oil-palm production destroying their precious habitat at an ever 5. ?

Explanation

Correct Answer: quickening

We need an adjective to describe the pace. Quickening indicates a speed that is becoming faster and faster.

(QUICK) pace, the animal is on the brink of extinction. Mass tourism itself must take part of the blame for the creature’s demise, but for anyone determined to see one, a 6. ?

Explanation

Correct Answer: rehabilitation

We need a noun to act as a modifier for the noun center. A rehabilitation center is a place that helps animals return to a normal life.

(REHABILITATE) center offers the chance to do so in a regulated environment. The recent discovery of a new population of orangutans in a largely 7. ?

Explanation

Correct Answer: inaccessible

An adjective is required to describe the area. Inaccessible means a place that is very difficult or impossible to reach.

(ACCESS) area of Borneo is a bit of positive news in an otherwise bleak situation. A team of conservationists has 8. ?

Explanation

Correct Answer: highlighted

After the auxiliary verb has, we need a past participle. Highlighted means to draw special attention to something important.

(LIGHT) the need to protect the group, both by 9. ?

Explanation

Correct Answer: discouraging

After the preposition by, we use the V-ing form. Discouraging means trying to prevent something from happening.

(COURAGE) unwanted tourists, and by ensuring the remote region remains 10. ?

Explanation

Correct Answer: untouched

After the verb remains, an adjective is needed. Untouched means not changed or damaged.

(TOUCH) by the sort of development that has done so much damage elsewhere.