Formal pairs suit Writing Task 2. Neutral ones work anywhere. Informal ones belong in Speaking.
1.target audience
neutralthe group of people a product or message is aimed at
Advertisers choose images that appeal to their target audience.
Reach and appeal to collocate with it.
2.launch an advertising campaign
neutralstart an organised series of adverts
The company launched an advertising campaign aimed at teenagers.
Run an advertising campaign is also natural.
3.the mass media
formaltelevision, newspapers, radio and the internet that reach large audiences
The mass media shapes how people see politics.
Takes a singular or plural verb; be consistent.
4.spread misinformation
formalpass on false or misleading information
Social media allows anyone to spread misinformation faster than journalists can correct it.
Spread fake news is more informal.
5.media coverage
neutralthe reporting of an event by newspapers, television and websites
The floods received extensive media coverage.
Receive, attract and extensive collocate with it.
6.hit the headlines
informalsuddenly become an important news story
The scandal hit the headlines within hours.
Good in Speaking. Make headlines is equally common.
7.freedom of the press
formalthe right of journalists to report news without government control
Freedom of the press is essential for holding governments to account.
Press freedom is the shorter form.
8.an invasion of privacy
neutralan unwelcome intrusion into someone's private life
Photographing celebrities' children is an invasion of privacy.
Invade someone's privacy is the verb form.
9.influence consumer behaviour
formalchange how people decide what to buy
Online reviews influence consumer behaviour more than traditional adverts.
British spelling: behaviour.
10.brand loyalty
neutrala customer's habit of buying the same brand
Supermarkets use reward cards to build brand loyalty.
Build and create collocate with it.
11.misleading claims
formalstatements that give a false impression
Adverts for diet products often contain misleading claims.
Make misleading claims; misleading advertising is the general term.
12.impulse buying
neutralbuying things suddenly without planning
Bright displays near the checkout encourage impulse buying.
An impulse purchase is a single item.
13.go viral
informalspread very quickly online
A short video can go viral and make an unknown singer famous overnight.
Speaking only, or in quotation marks in an essay.
14.a reliable source of information
neutrala source you can trust to be accurate
Many teenagers do not see television news as a reliable source of information any more.
Trustworthy is a close alternative to reliable.
15.news outlets
neutralorganisations that publish or broadcast news
Independent news outlets struggle to compete with free content online.
Media outlets is the broader term.