Reaching the initial target may be a stretch because some interior suppliers might not be able to increase the flow of high-quality parts fast enough to meet the Model X production plan, chief executive officer Elon Musk said on a conference call with analysts.
Utilize the input text as a context reference, choose the right relationship between 'Elon Musk' and 'chief executive officer' from the options.
Options: subsidiary, developer, owned by, position held