Refer to the input text as context and select the correct relationship between 'MTN Group' and 'MTN Nigeria' from the available options.
Options: subsidiary, creator, product/material produced, publisher

MTN Nigeria subscriber base increases but revenues drop MTN Group CEO , By MTHULISI SIBANDA JOHANNESBURG, (CAJ News ) – THE MTN Group has announced a decline in revenues at its Nigerian entity during the first half of the year.
subsidiary