Exam CIPP-E topic 1 question 37 discussion

SCENARIO -
Please use the following to answer the next question:
Due to rapidly expanding workforce, Company A has decided to outsource its payroll function to Company B. Company B is an established payroll service provider with a sizable client base and a solid reputation in the industry.
Company B’s payroll solution for Company A relies on the collection of time and attendance data obtained via a biometric entry system installed in each of Company A’s factories. Company B won’t hold any biometric data itself, but the related data will be uploaded to Company B’s UK servers and used to provide the payroll service. Company B’s live systems will contain the following information for each of Company A’s employees:

Name -

Address -

Date of Birth -

Payroll number -

National Insurance number -

Sick pay entitlement -
Maternity/paternity pay entitlement

Holiday entitlement -
Pension and benefits contributions

Trade union contributions -
Jenny is the compliance officer at Company A. She first considers whether Company A needs to carry out a data protection impact assessment in relation to the new time and attendance system, but isn’t sure whether or not this is required.
Jenny does know, however, that under the GDPR there must be a formal written agreement requiring Company B to use the time and attendance data only for the purpose of providing the payroll service, and to apply appropriate technical and organizational security measures for safeguarding the data. Jenny suggests that Company B obtain advice from its data protection officer. The company doesn’t have a DPO but agrees, in the interest of finalizing the contract, to sign up for the provisions in full. Company A enters into the contract.
Weeks later, while still under contract with Company A, Company B embarks upon a separate project meant to enhance the functionality of its payroll service, and engages Company C to help. Company C agrees to extract all personal data from Company B’s live systems in order to create a new database for Company B. This database will be stored in a test environment hosted on Company C’s U.S. server. The two companies agree not to include any data processing provisions in their services agreement, as data is only being used for IT testing purposes.
Unfortunately, Company C’s U.S. server is only protected by an outdated IT security system, and suffers a cyber security incident soon after Company C begins work on the project. As a result, data relating to Company A’s employees is visible to anyone visiting Company C’s website. Company A is unaware of this until Jenny receives a letter from the supervisory authority in connection with the investigation that ensues. As soon as Jenny is made aware of the breach, she notifies all affected employees.
The GDPR requires sufficient guarantees of a company’s ability to implement adequate technical and organizational measures. What would be the most realistic way that Company B could have fulfilled this requirement?