The person making the transfer is not necessarily the only payer.
Payroll includes the employee's share. The employer remits the contributions and also bears their own share. Looking only at the transfer to the collecting body therefore misses how the cost is divided.
The question asks generally about financing social insurance. Of the four options, “employers and employees” captures the basic principle; the others either omit an important contributor or rely on the wrong criterion.

The other three answers
“Only” and “all” make the incorrect answers too sweeping.
only employees
Employees are not the only contributors. Employers also bear their own contribution shares in ordinary employment.
all citizens
Contribution liability does not arise from citizenship alone. Insurance status, employment and further statutory conditions are decisive.
only employers
Employer-only funding applies to statutory accident insurance for employees, but does not generally describe all social insurance contributions.
The basic principle has important exceptions.
Health, long-term care, pension and unemployment insurance have rules for sharing contributions. Special forms of employment or additional contribution components can differ. “Always exactly fifty-fifty” would therefore be an inaccurate blanket statement.
Statutory accident insurance for employees is financed entirely by employers. Additional public funding also does not make “all citizens” the general contribution group sought by the question.
Contribution allocation · German Pension Insurance ↗Remember shared funding, with accident insurance as an exception.
Remittance, employee share and employer share are three different concepts.
Three words for this question
- der Arbeitgeberanteilemployer contribution share
- The part of a social insurance contribution borne by the employer.
- die Beitragstragungallocation of contribution costs
- The legal allocation of who bears which part of a contribution.
- die Unfallversicherungaccident insurance
- A statutory insurance branch whose contributions for employees are borne by employers alone.
