Why the other options are wrong:

• make antivirus software unnecessary.: The software is explicitly said to complement antivirus software, not make it unnecessary.
• speed up every transaction.: Transaction speed is not the stated purpose; the report concerns protection from hackers.
• avoid all future software updates.: HSBC recommends software updates rather than avoiding future updates.

Correct Answer: interacting with the customer's browser.

Why this is correct: The report says the software prevents hackers interacting with the browser the customer is using. This is the specific mechanism described.

Why the other options are wrong:

• replacing the bank's antivirus programme.: The stated mechanism protects the customer's browser, not the bank's antivirus programme from replacement.
• downloading updates from any website.: Blocking downloads of updates is not stated; customers are advised to install security updates.
• changing the bank's web address for all users.: The report does not describe changing the bank's web address for all users; it identifies interaction with the customer's browser.

Correct Answer: exceeded the bank's most optimistic expectations.

Why this is correct: The security manager says download rates surpassed the bank's most optimistic expectations. Uptake was higher than anticipated.

Why the other options are wrong:

• fallen below the bank's expectations.: The rates surpassed even optimistic expectations rather than falling below them.
• stopped before any customers could get the software.: A high volume of customers obtained the software, so downloads did not stop before anyone could get it.
• remained at zero.: The reported high uptake contradicts zero downloads.

Correct Answer: keep their antivirus software updated.

Why this is correct: HSBC specifically advises customers to keep antivirus software updated because new viruses are created frequently. Browser protection complements it.

Why the other options are wrong:

• stop using antivirus once this software is installed.: The new software complements antivirus software rather than making it unnecessary.
• ignore software updates.: Ignoring updates contradicts HSBC's advice to keep security software updated.
• only update their web browser.: The advice explicitly includes antivirus updates; it is not confined to the browser.

Correct Answer: log on through a link in a phishing email.

Why this is correct: The recovered ending says phishing emails may urge customers to log on through an emailed link and that HSBC will never ask them to do this. The answer keeps the phishing-email context.

Why the other options are wrong:

• ignore all browser updates.: The report recommends software updates; it does not identify ignoring browser updates as the request discussed in the final warning.
• stop using current antivirus software.: The software complements antivirus protection, and the report advises keeping antivirus updated. Stopping it is not the action identified by the final warning.
• avoid every link to an external website.: The report warns about phishing-email logon links, not every link to an external website.